A thought experiment that includes a square light clock is similar to the traditional vertical light beam and mirror clock, except it is made up of four mirrors placed at a 45° angle at each corner of a square of length L0, shown in Fig. 1. Here we have shown the events as measured in the rest frame of the square light clock. By studying the same cycle of events measured in a frame of reference where the square light clock is in motion with speed of v, we can derive both time dilation and, independently, length contraction. This will be done by analyzing the changing dimensions and also the one-cycle timing for this square light clock.